2000
#4,336
National surname rank
Recorded bearers 7,580
First available Census row
Per 100,000 2.81
Uncommon Last name
Delrio
Of Spanish origin, referring to someone who lived near a river or stream.
According to the 2020 US Census Bureau surname tables, roughly 11,249 Americans carry the last name Delrio. That puts it at #3,548 in the national surname ranking, appearing at a frequency of 3.28 per 100,000 people (about 1 in 30,470 residents).
This page is the full Name Census profile for the Delrio surname. You will find the Census Bureau frequency data, a multi-census history view, an ancestry and ethnicity breakdown based on self-reported demographics, the name's meaning and origin where available, and answers to the most common questions people ask about this surname.
Bearers in the US
11K
1 in 30,470
Census rank
#3,548
2020 decennial data
Per 100,000
3.3
Frequency rate
Recorded bearers
9.8K
uncommon in the US
Popularity narrative
The Census Bureau recorded 9,810 bearers of the surname Delrio in its 2020 decennial surname file. At a rate of 3.28 per 100,000 residents, it holds the 3548th position in the national surname ranking.
Among Census respondents with the surname Delrio, the largest self-reported group is Hispanic at 88.3%. The next largest groups are White (9.0%) and Asian/Pacific Islander (1.1%).
Origin
Meaning and origin of Delrio
The surname DELRIO is of Spanish origin, with its roots tracing back to the regions of Andalusia and Castile in the late 15th century. The name is believed to be derived from the Spanish words "del" and "rio," which together translate to "of the river" or "from the river." This suggests that the earliest bearers of this surname may have lived near a prominent river or worked in occupations related to rivers or waterways.
One of the earliest recorded instances of the DELRIO name can be found in the archives of the Kingdom of Castile in 1492, where a merchant named Juan DELRIO is mentioned in a trade document. This suggests that the name was already in use during the reign of the Catholic Monarchs, Ferdinand and Isabella.
In the 16th century, the DELRIO name gained prominence with the birth of Martín Antonio DELRIO (1551-1608), a Jesuit scholar and writer known for his works on demonology and witchcraft. His treatise "Disquisitionum Magicarum Libri Sex" (Six Books on Investigations into Magic) was widely influential in the understanding of witchcraft during the Inquisition.
Another notable figure with the DELRIO surname was Pedro DELRIO (1624-1708), a Spanish painter and engraver who worked in the Baroque style. His works can be found in various churches and museums across Spain, including the Museo del Prado in Madrid.
In the 18th century, the DELRIO name appeared in the records of the Spanish colonization of the Americas, with a captain named Diego DELRIO leading an expedition to establish settlements in present-day Argentina in 1779.
Moving into the 19th century, Juan DELRIO (1804-1878) was a notable Spanish politician and writer who served as a member of the Spanish Parliament and published several works on philosophy and literature.
Throughout history, variations of the DELRIO name have also been documented, such as DELRÍO, DEL RÍO, and DE RÍO, reflecting regional spelling differences and the evolution of the Spanish language over time.
While these historical accounts provide insight into the origins and notable bearers of the DELRIO surname, it is important to note that genealogical records and documentation from earlier periods may be incomplete or subject to interpretation.
Demographics
Ancestry and ethnicity for Delrio
Among Census respondents with the surname Delrio, the largest self-reported group is Hispanic at 88.3%. The next largest groups are White (9.0%) and Asian/Pacific Islander (1.1%).
The bar chart below shows how Delrio bearers described their own race and ethnicity on the 2020 Census form. The Census Bureau groups responses into six broad categories: White, Black or African American, Hispanic or Latino, Asian and Pacific Islander, American Indian and Alaska Native, and Two or More Races. When a category has too few respondents for a given surname, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown for every Census year so the breakdown stays comparable over time. When the source file also includes raw headcounts, Name Census shows those alongside the percentages in the legend.
Keep in mind that these are self-reported numbers. A person's surname does not determine their race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the Delrio surname at the time of the 2020 Census, not any inherent property of the name itself.
- Hispanic or Latino88.3% · 8,659
- White9.0% · 881
- Asian and Pacific Islander1.1% · 106
- Black or African American0.8% · 82
- Two or more races0.6% · 59
- American Indian and Alaska Native0.2% · 23
Timeline
Historical Census data for Delrio
Delrio appears in 3 published Census surname files: 2000, 2010, 2020. The cards below show how the name's rank and bearer count changed across each release.
2010
#3,620
National surname rank
Recorded bearers 9,814
+2,234 bearers (+29.5%)
Per 100,000 3.33
Rank movement Up 716 places
2020
#3,548
National surname rank
Recorded bearers 9,810
-4 bearers (-0.0%)
Per 100,000 3.28
Rank movement Up 72 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #4,336 | 7,580 | 2.81 | First available Census row | First available Census row |
| 2010 | #3,620 | 9,814 | 3.33 | +2,234 bearers (+29.5%) | Up 716 places |
| 2020 | #3,548 | 9,810 | 3.28 | -4 bearers (-0.0%) | Up 72 places |
For 2020, the Census Bureau published race and Hispanic-origin columns as counts rather than percentages. Name Census converts those counts back into shares so the ancestry section stays comparable with the older surname files.
Year on year
2010 vs 2020 Census
How has the Delrio surname changed between Census years? The chart shows bearer count side by side, and the table compares rank, count, and frequency.
Census year comparison
20102020
| Metric | 2010 | 2020 | Change |
|---|---|---|---|
| Rank | #3,620 | #3,548 | 2.0% |
| Count | 9,814 | 9,810 | -0.0% |
| Per 100K | 3.33 | 3.28 | -1.4% |
Between the 2010 and 2020 Census, the number of Delrio bearers went from 9,814 to 9,810 (+-0.0% change). The surname moved up 72 positions in the national ranking, going from #3,620 to #3,548.
Notable bearers
Famous people with the surname Delrio
FAQ
Delrio surname: questions and answers
How many people in the U.S. have the surname Delrio?
Name Census estimates that about 11,249 living Americans carry the surname Delrio. Using the current population baseline, that works out to roughly 1 in 30,470 residents.
How common is Delrio?
Delrio ranks #3,548 in the 2020 Census surname tables and is classified on this site as "Uncommon." The Census recorded the name at a frequency of 3.28 per 100,000 residents, which is about 3 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 9,810 people with the surname Delrio. That is different from the site's living-bearer estimate (11,249), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 3.28 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 3.28 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 3 of them to have the surname Delrio.
Has Delrio become more or less common over time?
Between 2010 and 2020, the surname Delrio went from 9,814 recorded bearers to 9,810. That is a decrease of 4 (-0.0%). In the national ranking it rose from #3,620 to #3,548.
What does the Census say about the background of Delrio?
Among Census respondents with the surname Delrio, the largest self-reported group is Hispanic at 88.3%. The next largest groups are White (9.0%) and Asian/Pacific Islander (1.1%). These figures come from the 2020 Census Bureau surname tables, based on how respondents described their own race and ethnicity.
Which group reports this surname most often?
Hispanic is the largest self-reported group for the surname Delrio in the 2020 Census, accounting for 88.3% (8,659 people in the source table).
What is the full ancestry breakdown?
Delrio appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Hispanic (88.3%), White (9.0%), Asian/Pacific Islander (1.1%). For 2020, the source file also published raw headcounts for each group, which is why this page can show both percentages and counts in the ancestry section.
Is this page using the latest Census data?
Yes. This page is using the latest surname file currently loaded on Name Census, which is 2020. The historical section above also keeps any older Census surname entries we have for Delrio (2000, 2010, 2020).
Does the Census include every surname?
No. The Census Bureau only publishes surnames that appeared at least 100 times in a given decennial Census. That means very rare surnames are excluded entirely, and a surname can appear in one Census release but disappear from a later one if it falls below the reporting threshold.
Why don't the ancestry percentages always add up to exactly 100%?
There are two main reasons: rounding and suppression. The Census Bureau rounds published values, and it may suppress very small cells to protect privacy. For 2020, the Bureau also published raw group counts rather than direct percentages, so Name Census converts those counts back into shares for comparability across census years.
What does Delrio mean?
Of Spanish origin, referring to someone who lived near a river or stream. The fuller origin note on this page goes into more detail.
Where does the surname data come from?
All surname statistics on Name Census are drawn from the US Census Bureau's decennial surname frequency tables. These files list every surname that appeared 100 or more times in the 2020 Census, along with a count, a per-100,000 rate, and a self-reported demographic breakdown. You can read the full explanation on our methodology page.
How does Name Census estimate living bearers?
For surnames, Name Census does not age cohorts the way it does for first names. Instead, it takes the Census Bureau's published frequency for Delrio (3.28 per 100,000) and applies that rate to the current U.S. resident population to estimate how many living Americans have the surname today.
How many people have the last name Delrio?
You can see how many people are called Delrio on our sister site HowManyOfMe.org — same data roots, lighter UI.